FS Series Vertical Float Switches
Quick Overview
The FS Series vertical float switch is SMD's most versatile liquid level sensor — available as a single-point switch or as a multi-level assembly with up to four switch points on a single stem. A buoyant float slides along the stem and its internal permanent magnet actuates the hermetically sealed reed switch at the configured level. Available in stainless steel (303, 304, 316L) and engineering plastics including polypropylene, PVDF, Kynar, and nylon. An optional integrated NTC or PT100 thermistor provides simultaneous temperature sensing in a single unit — ideal for HVAC, boiler, and cooling circuit monitoring.
Specifications
| Orientation | Vertical / top or bottom mount |
| Technology | Magnetic reed switch |
| Switch Points | Single or multi-level |
| Housing Materials | Stainless steel (303/304/316L), polypropylene, PVDF, Kynar, Nylon |
| Switch Type | SPST (NO or NC) / SPDT |
| Cable | Custom lengths available |
| Mounting | NPT or BSP threaded; flange and custom available |
| Options | Level + temperature combo available |
| Certifications | ISO 9001 |
Key Features
Vertical Top or Bottom Mount
Install from the top or bottom of any tank — stem length and float position are fully configurable to your set point.
Magnetic Reed Technology
Hermetically sealed reed switch inside the stem — no liquid contact with switch electronics for reliable long-term operation.
Wide Material Selection
Stainless steel 303, 304, or 316L and engineering plastics (PP, PVDF, Kynar, nylon) for chemical and temperature compatibility.
Single and Multi-Level
Order single-point switches or multi-level assemblies with 2, 3, or 4 switch points on one stem — reduces installation hardware.
Level + Temperature Combo
Integrated NTC or PT100 thermistor option adds temperature sensing in the same unit for HVAC, coolant, and process tanks.
OEM Volume Pricing
Designed for production OEM quantities with custom stem lengths, floats, cable, connectors, and packaging.
Related Products
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View productReady to specify an FS Series float switch?
Our engineering team can help with material selection, stem length, and custom OEM configurations.